Fuel-oil burner



Feb. 12, 1929.

L. E. JOHNSON FUEL OIL BURNER Filed April 16, 1926 3 Sheets-Sheet 1 Dwenlor:

l a/wrc Efihuon ,diiy.

Feb. 12, 1929. 1,702,162

L. E. JOHNSON FUEL OIL BURNER Filed April 16, 1926 5 sheets-sheet 2 Feb. 12, 1929. 1,702,162

L. E. JOHNSON FUEL OIL BURNER FiledApril 16, 1926 5 Sheets-Sheet 3 Jiiiyb Patented Feb. 12, 1929.

UNITED STATES 1,702,162 PATENT OFFICE.

LAWRENCE E. JOHNSON, OF MELROSE, MASSACHUSETTS, ASSIGNOR TO UNITED SHOE MACHINERY CORPORATION, OF PATEBSON, NEW JERSEY, A CORPORATION OF NEW JERSEY.

FUEL-OIL BURNER.

' in the art, the invention comprises the features and combinations of parts hereinafter described and then particularly pointed out in the appended claims.

The features and scope of the invention will best be understood from a description of the preferred embodiment thereof illustrated in the accompanying drawings, in

* which:

Figure 1 is a front elevation of the entire housing and combustion chamber with a p01 tion of the burner bowl broken away to show certain parts within the combustion chamber;

Fig. 2 is an enlarged plan view illustrating the burner section of the housing;

Fig. 3 is an enlarged vertical sectlon taken on the line 33 of Fig. 1;

Fig. 4 is a detail in vertical section showing how a pilot may be used in the combustion chamber;

Fig. 5 is a plan'view of the base section of the housing; and

Fig. 6 is a broken section taken on the line 6-45 of Fig. 5.

The embodiment of the invention illus trated in the drawings comprises a. burner housing having a cold air compartment formed within its lower portion and into which a supply of cold air is introduced in any approved manner. The fuel oil is supplied to a discharge nozzle located within the cold air compartment of the housing. and provision is made for causing the cold air to flow past the nozzle in a manner to cool the incoming oil and to insure a mixture of the cold air and-the discharged fuel oil as the air is forced upwardly and outwardly toward the combustion chamber where the mixture is ignited.' Provision is preferably made for lay-passing a portion of the cold air from the air chamber to a hollow heating plate and then discharge it substantially radially into the combustion chamber from below the heating plate. The air thus heated is caused to impinge and mingle with the flame, assisting in the combustion ofthe fuel oil by supporting the so-called secondary combustion and, because of the manner in which it is introduced, insuring most efficient and complete combustion of the mixture. 7

Referring now to Figs. 1 and 3 of the drawings, in order that the burner may be readily assembled, it is preferably made in five sections. These comprise (1) a base section 10 supported on diametrically opposite legs 11, (2) an air chamber section 12 mounted on the base section and secured a to it by bolts 19, an intermediate burner section 13 mounted on the section 12 and secured to it by bolts passing through holes 15 formed in the burner section. (4) abowl-shaped rim section 14 lined with heat resisting material mounted on a flange formed on the upper portion of the burner section and adapted to form the outer portion of a combustion chamber. and (5) an upper flame spreader supported by means of legs 31 and 36 provided with reces es which fit over annular flanges 37 formed on the upper faces of lugs 33 on the. burner section 13. This construction of burner, it

will be observed, may be readily assembled and also the construction is such as to facilitate the manufacture thereof, thus enabling the burner to be marketed at a reasonable price.

The base section 10, the air chamber section 1:2, and the burner section 13 cooperate to form an enclosed air chamber 22 into which cold air is introduced, preferably under pressure, through an air inlet pipe 18 secured to the housing by a flange 16 which branches into oppositely arranged passages 20 formed by cooperating. channels in the base section 10 and its superposed section 12, as best illustrated in Figs. 3 and 5.

Fuel oil is fed to the burner from any suitable source of supply through an oil inlet pipe 49 which is preferably arranged, as illustrated in Fig. 3, to communicate with the horizontal branch of an L-shaped passage 48 formed centrally in the base sec- I sageway 29 to the pilot 80, or 11 any other tion 10. The oil passes from the vertical branch of the passage 4L8, through a connected vertical pipe a7, and is discharged through a nozzle 59 secured in the upper end of the pipe M. llnasmuch as the entire oil inlet pipe and discharge nozzle are located in or adjacent to the cold air chamber 22, carboniaation of the oil in the pipe and nozzle is efi'ectively prevented.

Provision is made for causing the cold air introduced to the chamber 22 to flow in the form of a turbulent annular stream at high velocity and around and past the discharge nozzle 50 in order that the fuel oil being discharged may be aspirated by the surrounding current of air to become thoroughly mixed therewith. As herein illustrated the cold air is caused to flow through an annular passage formed between coopcrating faces of a specially shaped block 46 secured upon the upper portion of the pipe 47 immediately below the discharge nozzle 50, and the walls of a cooperating sleeve 52 located in a central opening or hub formed in the batlie at the bottom of the burner section 13. As illustrated in Fig. 3 the block 46 is formed as a double truncated cone with the two bases abutting,

being held on the pipe 47 by a set screw,

and the sleeve 52 is so shaped as to provide a central space in the form of a double truncated cone with the two apexes abutting similar to a venturi. The lower half of this space forms a circular wall tapering downwardly and outwardly that is parallel to the upwardly and inwardly tapering wall of upper half of the block 46. Thus an annular air conduit is formed that conducts cold air from all sides, by cross currents, to the oil nozzle 50 and then provides for immediate expansion and deflection, just prior 1 and leads into a passage 25 communicating to the mixture entering the combustion chamber, by reason of the interposition of the oppositely tapered or fiaring'opening 51 which serves also to guide the stream upwardly and outwardly under the flame spreader 35. The oil is thus aspirated or entrained by the flowing air, is aided in vaporizing by the reduced air pressure, and is thoroughly broken up and mixed with the air prior to ignition.

The fuel oil carried by the coldair stream may be ignited by a pilot 30, herein shown as supplied with gas from agas pipe 28 leading from a gas supply through a pasapproved manner.

Provision is made for heating a port-ion of the air supplied through the air inlet pipe 18, and for thereafter directing the heated air into the ignited vapor, air, and finely divided oil, to supply at the proper point additional oxygen to increase the heat of combustion at the center of the flame mass. For this purpose passages 38 are provided in the legs 34: and 36 and in the section 12 of the burner, that lead. from the air chamber 22 to above the spreader plate 35 and into the space between it and a cover member d0, these two parts forming a hollow flame spreader. The cover member 10 has suspended from it a substantially coni cal baiiie d1 which functions to assist in the deflection of the stream of combustible vapor, air and finely divided oil and to cause it to pass outwardly under the spreader plate 35 and into the surrounding combustion chamber proper. Provision is made for conducting the heated air from the hollow flame spreader 2-35-40 through a central opening 57 in the spreader plate 3:) and thence radially outwardly in a sheet between the bottom surface of said plate and the upper surface of the baffle 41. The opening 57 is maintained by spacing lugs 59 upstanding from the battle 41, enabling the baffle and also the cover plate 40 to be rigidly secured in place by a clamping nut 42 threaded on the end of the bolt 61, as

shown in Fig. 3. The heated air thus caused to intermingle with and be dispersed through the flame of the ignited vapor, air and finely divided liquid oil aids materially in effecting combustion without causing a back-pressure to interfere with expansion in the flaring passage 51, so that as the stream of oil, vapor and hot and cold air flows laterally and outwardly under the spreader plate 35, perfect combustion of the fuel oil is accomplished as it passes to the space within the rim section 14.

For the purpose of drawing ofi any oil which may leak into the chamber 22; a cupshaped depression 23 is formed in the base of the chamber .22, and a passage 24 is formed in the bottom of the depression 23 gather in the lower portion of the burner section 13, the passage 25 is extended upwardly into the lower portion of this section, as shown in Fig. 6.

vThe term cold air in both the specificationand claims is not intended as limiting, but merely to distinguish the air which has not been heated in the hollow battle from that which has.

While it is preferred. to employ the spe cific construction and arrangement of parts shown and described it will be understood that this construction is not essential except so far as specified in the claims, and may be changed or modified without departing from the broader features of the invention.

VVhatis claimed as new, is

1. A fuel oil burner comprising a housing having a cold air chamber formed therein supplied with air under pressure, a nozzle discharging fluid fuel oil, a combustion chamber above said nozzle, means forming an annular air conduit surrounding the fuel oil discharge nozzle and through which cold air flows from said cold air chamber to the combustion chamber, an air-heating chamber Whose bottom wall forms a circular flame-spreader located above the fuel oil i discharge nozzle and in the path of the oil bearing stream of air, a by-pass conduit from said cold air chamber to said airheating chamber, and means for discharging the heated air in a radially diverging sheet into the combustion chamber under said flame-spreader.

2. In a fuel oil burner, a combustion chamber, a circular flame spreader located in the upper part of the combustion chamber, means for discharging a mixture of fuel oil and cold air into the combustion chamber, and means for discharging heated air in a radially diverging sheet into the combustion chamber under said circular flame-spreader. i

3. In a fuel -oil burner, a combustion chamber, a circular hollow flame spreader thereabove, means for discharging a mixture of fuel oil and cold air upwardly into the combustion chamber beneath and toward the center of the flame spreader, means for conducting air into "the interior .of said flame spreader to be heated, and

means for discharging the heated air in a radially diverging sheet beneath said flame spreader.

4. In a fuel oil burner, a combustion chamber having a circular hollow flame spreader thereabove, means for discharging a mixture of oil and cold air beneath and toward the center of the spreader, means for conducting air to the interior of the spreader to be heated, and means for causing said heated air to be discharged radially outwardly across the under surface of said flame spreader.

5. In a fuel oil burner, a combustion chamber having a circular hollow flame spreader thereabove, means for conducting air into the flame spreader to be heated, means for discharging a mixture of oil and air upwardly under the center of the surface of the flame spreader, and a deflecting battle supported by said flame spreader, said flame spreader having an opening to the combustion chamber for discharging the heated air laterally from behind said bafile. 6. In a fuel oil burner, a combustion chamber, a fuel discharge nozzle located discharge nozzle, means for conducting air to be heated into said hollow flame spreader, a central opening in the under-wall of said flame spreader, and means for deflecting the air passing through said opening laterally and radially undersaid flame spreader.

7. A fuel oil burner having, in combination, a combustion chamber having a central opening, a housing depending from' said chamber, an oil supply pipe within said housing having anozzle in said opening, a circular hollow flame spreader having an opening in its under-Wall above said nozzle, means for admitting air to said housing for discharge through said central opening about the nozzle and for conducting a portion of said air to the interior of said flame spreader, and means under said opening in the flame spreader for deflecting air passing therethrough laterally and radially into the combustion chamber.

8. A fuel oil burner comprising a housing providing a cold air chamber, a cold air inlet to the chamber, a fuel oil discharge nozzle above the chamber, means for directing cold air from the chamber past the nozzle to entrain the fluid fuel, a combustion chamber, a circular hollow flame spreader above the discharge nozzle and combustion chamber, a pair of oppositely-disposed by-pass conduits in the housing connecting the cold air chamber with the interior of the flame spreader, and means for directing heated air from the interior of the flame spreader to the combustion chamber in a radially diverging sheet centrally under said circular flamespreader.

9. In an oil burner of the type set forth, a fire-bowl, a pair of hollow legs standing therein, a circular hollow heating-chamber in communication with said legs and mounted thereon, this heating-chamber 'being set down in the bowl with its under surface serving as a flame-spreader, the center of said under wall being provided with a hole to conduct heated air downwardly to the under side of the flame-spreader, a balfle supported under said flame-spreader at a distance therefrom and in position to cover this hole, and means arranged below said baffle for jetting fuel and air upwardly against said bafile and for continuously supplying air under pressure to said hollow legs.

LAWRENCE E. JOHNSON. 

